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Things are getting interesting. So those reports of the BMW F82 M4 having 444 horsepower that had fanboys complaining? It is looking like it will have even less than that out of the gate with a claimed 416 horsepower. Please do not throw anything at your monitor. BMW is having fun charging twice for horsepower these days with "Performance" software swaps so it is basically a certainty that just like the M5/M6 the M3/M4 will have a Competition Package that should boost output above the 444 horse figure reported earlier with a claimed 35 horse gain from the package.

The F10 M5 and F12/F13 M6 need their horsepower and torque to move their huge asses, especially the M5 which is a fat pig. An emphasis on lighter weight is exactly what BMW needs. Frankly, it's long overdue but clearly BMW is responding to the warranted criticism. It is difficult to claim to be Efficient and Dynamic when the cars outweigh the competition.

If what AutoBild reports is true then the M4 will weigh 100 kilograms less than the standard 4-Series. That would mean a curb weight in the ~3300 pound range. It sounds almost too good to be true but with optional ceramic brakes and various lightweight body pieces they may hit that weight. That would make this the lightest M3 (shut up Bimmerboost knows they are calling it an M4) since the E36. Now that is something to be proud of. It also makes the F80 and F82 chassis designations versus the F30 for the 3-Series and the F32 for the 4-Series suddenly make sense if the construction materials differ greatly.

Other options other than the ceramic brakes and competition package include a valved exhaust system and 20 inch wheels. Oh, and a 6-speed manual option of course. The 7-speed DCT will not be forced on you (as it should not be in a drivers car).

This is much, much better than anticipated if accurate. It seems BMW is finally responding to the criticism of fat cars that no longer offer the best driving experience in their class. It is a certainty that the new W205 C63 AMG will outpower this car with its 4.0 liter twin turbo V8 but if the new M3 is significantly lighter it will not need as much power to compensate while at the same time running circles around the C63 AMG on the roadcourse.

Limp mode issues will still be a concern with the turbo motor on the track and we will have to just wait and see how it holds up in a racetrack environment.

BMW and M are certainly not back as that once special M shine and swagger will forever be diminished but this is at the very least (once again, providing it is accurate) a step back in the right direction after quite a long string of BMW and M disappointments. Let's all keep our fingers crossed.

how are you going to have 2 twin scroll turbos? there are only 6 exhaust ports. each turbo is going to get 3. twin scroll takes the exhaust gasses and sends them through a divided housing, one port is for quick response and the other is for top end. how are you going to divide 3 exhaust ports into 2 ports for the turbine housing? Yes the N63 does have 2 twin scroll turbos but..... it can divide the 4 exhaust ports on each side evenly, 2 per port in the turbine housing. runners for the smaller port are probably short in order to create higher velocity gasses to spool the turbo faster while the other runners are probably longer will less angle promoting better top end. bottom line is the S55 will not be twin-twin scroll. @VargasTurboTech please correct me if i'm way off here.

Answering from the Wisconsin woods for my one hour a day allowed internet time. They cannot be twin scroll. You need an even number of exhaust pulses to create the twin scroll effect, a TT I6 cannot be Twin Scroll. It will have turbos similar to the N54, they will be small twins. The TT V8 M5's use Twins scroll the 550's use the same turbos but non twin scroll. The guy saying you use a different turbine wheel for the Twinscroll design is also not correct, same turbine wheel, all the Twinscroll does it put the exhaust pulses in the correct order so they do not fight each other and make them more efficient.

Answering from the Wisconsin woods for my one hour a day allowed internet time. They cannot be twin scroll. You need an even number of exhaust pulses to create the twin scroll effect, a TT I6 cannot be Twin Scroll. It will have turbos similar to the N54, they will be small twins. The TT V8 M5's use Twins scroll the 550's use the same turbos but non twin scroll. The guy saying you use a different turbine wheel for the Twinscroll design is also not correct, same turbine wheel, all the Twinscroll does it put the exhaust pulses in the correct order so they do not fight each other and make them more efficient.

But what if they were to a do a manifold that would evenly split exhaust gases for even exhaust pulses similar to what they do with the S63? I mean you can have a single turbo I6 twin scroll right?

But what if they were to a do a manifold that would evenly split exhaust gases for even exhaust pulses similar to what they do with the S63? I mean you can have a single turbo I6 twin scroll right?

When you figure out how to divide 3 and get an even number, let the world know, I think some math scholars would like to hire your for their staff. Its not possible, so you have 1.5 exhaust ports going into each scroll?

When you figure out how to divide 3 and get an even number, let the world know, I think some math scholars would like to hire your for their staff. Its not possible, so you have 1.5 exhaust ports going into each scroll?

it is possible to do it yes. i think it would actually perform worse than TT single scroll though. it would prob be more laggy and have the same topend becuase it has less exhaust gas for spoolup and less for topend.

Originally Posted by Sticky

I understand but in theory would that not allow two twin scroll turbos on an I6?

it is possible to do it yes. i think it would actually perform worse than TT single scroll though. it would prob be more laggy and have the same topend becuase it has less exhaust gas for spoolup and less for topend.

I understand what you are saying but if anyone could solve the engineering issues with this it would be BMW considering what we have seen from their turbo manifolds thus far. Just want to point out it isn't in theory impossible to have a twin turbo twin scroll I6 just that it would be very difficult to do and may not even be efficient.

You missed the main point and it is not fuel efficiency nor peak HP. A loss of 220 lbs over the 4 series variant (if true) is a major improvement and is "///M philosophy" to a T. Shave 220 lbs from your E9X M3 or E46 M3 and change NOTHING else - and it will transform the driving dynamics of the car - acceleration, handling, turn-in and braking.

Secondly, the throttle response component you mention is mere speculation. I doubt the difference in responsiveness between the outgoing powerplant and the new one is the chasm you implied. The motor will be less responsive than the N/A V8 no doubt - but not on par with the turbo-lag conspiracy I have been hearing from E9X owners. If we use the current turbo charged motors in the fleet as a comparison - F30 328, 335, and the 328d - we should be expecting slightly better responsiveness to merit the M badge.

I want to see the final weight of the sedan, and a stock dyno plot (particularly the torque curve) before I cast final judgement and a deposit.

Right - so my point stands. Every motor from M GmBH has been NA - for the exact same reason that the GT3 uses an NA engine, but the GT2 doesn't. Because a purist's sports car should have razor sharp throttle response to balance the car mid-corner (amongst other things) - with a turbocharged car, this simply can't be done. You cannot have the same response - therefore, I don't understand their decision. That's all I mean. They are dropping 2 cylinders and adding a turbo for sake of efficiency - and they don't need to do this. This is their proper sports car. I am sure the throttle response WILL be much improved as you allude, but I just don't think any turbo motor is going to be like a NA motor. The Nissan motor in the MP4 is one I would love to check out - it's supposedly really good. I just think they are taking steps back on the engineering in the motor department - however, yes - the chassis will be phenominal - I would be my car on it.

Right - so my point stands. Every motor from M GmBH has been NA - for the exact same reason that the GT3 uses an NA engine, but the GT2 doesn't. Because a purist's sports car should have razor sharp throttle response to balance the car mid-corner (amongst other things) - with a turbocharged car, this simply can't be done. You cannot have the same response - therefore, I don't understand their decision. That's all I mean. They are dropping 2 cylinders and adding a turbo for sake of efficiency - and they don't need to do this. This is their proper sports car. I am sure the throttle response WILL be much improved as you allude, but I just don't think any turbo motor is going to be like a NA motor. The Nissan motor in the MP4 is one I would love to check out - it's supposedly really good. I just think they are taking steps back on the engineering in the motor department - however, yes - the chassis will be phenominal - I would be my car on it.